/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/

#include "test_tcp_oos.h"

#include "lwip/tcp_impl.h"
#include "lwip/stats.h"
#include "tcp_helper.h"

#if !LWIP_STATS || !TCP_STATS || !MEMP_STATS
#error "This tests needs TCP- and MEMP-statistics enabled"
#endif
#if !TCP_QUEUE_OOSEQ
#error "This tests needs TCP_QUEUE_OOSEQ enabled"
#endif

/** CHECK_SEGMENTS_ON_OOSEQ:
 * 1: check count, seqno and len of segments on pcb->ooseq (strict)
 * 0: only check that bytes are received in correct order (less strict) */
#define CHECK_SEGMENTS_ON_OOSEQ 1

#if CHECK_SEGMENTS_ON_OOSEQ
#define EXPECT_OOSEQ(x) EXPECT(x)
#else
#define EXPECT_OOSEQ(x)
#endif

/* helper functions */

/** Get the numbers of segments on the ooseq list */
static int tcp_oos_count(struct tcp_pcb *pcb)
{
	int num = 0;
	struct tcp_seg *seg = pcb->ooseq;
	while (seg != NULL) {
		num++;
		seg = seg->next;
	}
	return num;
}

/** Get the numbers of pbufs on the ooseq list */
static int tcp_oos_pbuf_count(struct tcp_pcb *pcb)
{
	int num = 0;
	struct tcp_seg *seg = pcb->ooseq;
	while (seg != NULL) {
		num += pbuf_clen(seg->p);
		seg = seg->next;
	}
	return num;
}

/** Get the seqno of a segment (by index) on the ooseq list
 *
 * @param pcb the pcb to check for ooseq segments
 * @param seg_index index of the segment on the ooseq list
 * @return seqno of the segment
 */
static u32_t tcp_oos_seg_seqno(struct tcp_pcb *pcb, int seg_index)
{
	int num = 0;
	struct tcp_seg *seg = pcb->ooseq;

	/* then check the actual segment */
	while (seg != NULL) {
		if (num == seg_index) {
			return seg->tcphdr->seqno;
		}
		num++;
		seg = seg->next;
	}
	fail();
	return 0;
}

/** Get the tcplen (datalen + SYN/FIN) of a segment (by index) on the ooseq list
 *
 * @param pcb the pcb to check for ooseq segments
 * @param seg_index index of the segment on the ooseq list
 * @return tcplen of the segment
 */
static int tcp_oos_seg_tcplen(struct tcp_pcb *pcb, int seg_index)
{
	int num = 0;
	struct tcp_seg *seg = pcb->ooseq;

	/* then check the actual segment */
	while (seg != NULL) {
		if (num == seg_index) {
			return TCP_TCPLEN(seg);
		}
		num++;
		seg = seg->next;
	}
	fail();
	return -1;
}

/** Get the tcplen (datalen + SYN/FIN) of all segments on the ooseq list
 *
 * @param pcb the pcb to check for ooseq segments
 * @return tcplen of all segment
 */
static int tcp_oos_tcplen(struct tcp_pcb *pcb)
{
	int len = 0;
	struct tcp_seg *seg = pcb->ooseq;

	/* then check the actual segment */
	while (seg != NULL) {
		len += TCP_TCPLEN(seg);
		seg = seg->next;
	}
	return len;
}

/* Setup/teardown functions */

static void tcp_oos_setup(void)
{
	tcp_remove_all();
}

static void tcp_oos_teardown(void)
{
	tcp_remove_all();
}

/* Test functions */

/** create multiple segments and pass them to tcp_input in a wrong
 * order to see if ooseq-caching works correctly
 * FIN is received in out-of-sequence segments only */
START_TEST(test_tcp_recv_ooseq_FIN_OOSEQ)
{
	struct test_tcp_counters counters;
	struct tcp_pcb *pcb;
	struct pbuf *p_8_9, *p_4_8, *p_4_10, *p_2_14, *p_fin, *pinseq;
	char data[] = {
		1, 2, 3, 4,
		5, 6, 7, 8,
		9, 10, 11, 12,
		13, 14, 15, 16
	};
	ip_addr_t remote_ip, local_ip;
	u16_t data_len;
	u16_t remote_port = 0x100, local_port = 0x101;
	struct netif netif;
	LWIP_UNUSED_ARG(_i);

	/* initialize local vars */
	memset(&netif, 0, sizeof(netif));
	IP4_ADDR(&local_ip, 192, 168, 1, 1);
	IP4_ADDR(&remote_ip, 192, 168, 1, 2);
	data_len = sizeof(data);
	/* initialize counter struct */
	memset(&counters, 0, sizeof(counters));
	counters.expected_data_len = data_len;
	counters.expected_data = data;

	/* create and initialize the pcb */
	pcb = test_tcp_new_counters_pcb(&counters);
	EXPECT_RET(pcb != NULL);
	tcp_set_state(pcb, ESTABLISHED, &local_ip, &remote_ip, local_port, remote_port);

	/* create segments */
	/* pinseq is sent as last segment! */
	pinseq = tcp_create_rx_segment(pcb, &data[0], 4, 0, 0, TCP_ACK);
	/* p1: 8 bytes before FIN */
	/*     seqno: 8..16 */
	p_8_9 = tcp_create_rx_segment(pcb, &data[8], 8, 8, 0, TCP_ACK | TCP_FIN);
	/* p2: 4 bytes before p1, including the first 4 bytes of p1 (partly duplicate) */
	/*     seqno: 4..11 */
	p_4_8 = tcp_create_rx_segment(pcb, &data[4], 8, 4, 0, TCP_ACK);
	/* p3: same as p2 but 2 bytes longer */
	/*     seqno: 4..13 */
	p_4_10 = tcp_create_rx_segment(pcb, &data[4], 10, 4, 0, TCP_ACK);
	/* p4: 14 bytes before FIN, includes data from p1 and p2, plus partly from pinseq */
	/*     seqno: 2..15 */
	p_2_14 = tcp_create_rx_segment(pcb, &data[2], 14, 2, 0, TCP_ACK);
	/* FIN, seqno 16 */
	p_fin = tcp_create_rx_segment(pcb, NULL, 0, 16, 0, TCP_ACK | TCP_FIN);
	EXPECT(pinseq != NULL);
	EXPECT(p_8_9 != NULL);
	EXPECT(p_4_8 != NULL);
	EXPECT(p_4_10 != NULL);
	EXPECT(p_2_14 != NULL);
	EXPECT(p_fin != NULL);
	if ((pinseq != NULL) && (p_8_9 != NULL) && (p_4_8 != NULL) && (p_4_10 != NULL) && (p_2_14 != NULL) && (p_fin != NULL)) {
		/* pass the segment to tcp_input */
		test_tcp_input(p_8_9, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 8);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 9);	/* includes FIN */

		/* pass the segment to tcp_input */
		test_tcp_input(p_4_8, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 4);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 4);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 1) == 8);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 1) == 9);	/* includes FIN */

		/* pass the segment to tcp_input */
		test_tcp_input(p_4_10, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* ooseq queue: unchanged */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 4);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 4);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 1) == 8);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 1) == 9);	/* includes FIN */

		/* pass the segment to tcp_input */
		test_tcp_input(p_2_14, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 15);	/* includes FIN */

		/* pass the segment to tcp_input */
		test_tcp_input(p_fin, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* ooseq queue: unchanged */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 15);	/* includes FIN */

		/* pass the segment to tcp_input */
		test_tcp_input(pinseq, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 1);
		EXPECT(counters.recv_calls == 1);
		EXPECT(counters.recved_bytes == data_len);
		EXPECT(counters.err_calls == 0);
		EXPECT(pcb->ooseq == NULL);
	}

	/* make sure the pcb is freed */
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 1);
	tcp_abort(pcb);
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 0);
}

END_TEST
/** create multiple segments and pass them to tcp_input in a wrong
 * order to see if ooseq-caching works correctly
 * FIN is received IN-SEQUENCE at the end */
START_TEST(test_tcp_recv_ooseq_FIN_INSEQ)
{
	struct test_tcp_counters counters;
	struct tcp_pcb *pcb;
	struct pbuf *p_1_2, *p_4_8, *p_3_11, *p_2_12, *p_15_1, *p_15_1a, *pinseq, *pinseqFIN;
	char data[] = {
		1, 2, 3, 4,
		5, 6, 7, 8,
		9, 10, 11, 12,
		13, 14, 15, 16
	};
	ip_addr_t remote_ip, local_ip;
	u16_t data_len;
	u16_t remote_port = 0x100, local_port = 0x101;
	struct netif netif;
	LWIP_UNUSED_ARG(_i);

	/* initialize local vars */
	memset(&netif, 0, sizeof(netif));
	IP4_ADDR(&local_ip, 192, 168, 1, 1);
	IP4_ADDR(&remote_ip, 192, 168, 1, 2);
	data_len = sizeof(data);
	/* initialize counter struct */
	memset(&counters, 0, sizeof(counters));
	counters.expected_data_len = data_len;
	counters.expected_data = data;

	/* create and initialize the pcb */
	pcb = test_tcp_new_counters_pcb(&counters);
	EXPECT_RET(pcb != NULL);
	tcp_set_state(pcb, ESTABLISHED, &local_ip, &remote_ip, local_port, remote_port);

	/* create segments */
	/* p1: 7 bytes - 2 before FIN */
	/*     seqno: 1..2 */
	p_1_2 = tcp_create_rx_segment(pcb, &data[1], 2, 1, 0, TCP_ACK);
	/* p2: 4 bytes before p1, including the first 4 bytes of p1 (partly duplicate) */
	/*     seqno: 4..11 */
	p_4_8 = tcp_create_rx_segment(pcb, &data[4], 8, 4, 0, TCP_ACK);
	/* p3: same as p2 but 2 bytes longer and one byte more at the front */
	/*     seqno: 3..13 */
	p_3_11 = tcp_create_rx_segment(pcb, &data[3], 11, 3, 0, TCP_ACK);
	/* p4: 13 bytes - 2 before FIN - should be ignored as contained in p1 and p3 */
	/*     seqno: 2..13 */
	p_2_12 = tcp_create_rx_segment(pcb, &data[2], 12, 2, 0, TCP_ACK);
	/* pinseq is the first segment that is held back to create ooseq! */
	/*     seqno: 0..3 */
	pinseq = tcp_create_rx_segment(pcb, &data[0], 4, 0, 0, TCP_ACK);
	/* p5: last byte before FIN */
	/*     seqno: 15 */
	p_15_1 = tcp_create_rx_segment(pcb, &data[15], 1, 15, 0, TCP_ACK);
	/* p6: same as p5, should be ignored */
	p_15_1a = tcp_create_rx_segment(pcb, &data[15], 1, 15, 0, TCP_ACK);
	/* pinseqFIN: last 2 bytes plus FIN */
	/*     only segment containing seqno 14 and FIN */
	pinseqFIN = tcp_create_rx_segment(pcb, &data[14], 2, 14, 0, TCP_ACK | TCP_FIN);
	EXPECT(pinseq != NULL);
	EXPECT(p_1_2 != NULL);
	EXPECT(p_4_8 != NULL);
	EXPECT(p_3_11 != NULL);
	EXPECT(p_2_12 != NULL);
	EXPECT(p_15_1 != NULL);
	EXPECT(p_15_1a != NULL);
	EXPECT(pinseqFIN != NULL);
	if ((pinseq != NULL) && (p_1_2 != NULL) && (p_4_8 != NULL) && (p_3_11 != NULL) && (p_2_12 != NULL)
		&& (p_15_1 != NULL) && (p_15_1a != NULL) && (pinseqFIN != NULL)) {
		/* pass the segment to tcp_input */
		test_tcp_input(p_1_2, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 2);

		/* pass the segment to tcp_input */
		test_tcp_input(p_4_8, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 1) == 4);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 1) == 8);

		/* pass the segment to tcp_input */
		test_tcp_input(p_3_11, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 2);
		/* p_3_11 has removed p_4_8 from ooseq */
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 1) == 3);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 1) == 11);

		/* pass the segment to tcp_input */
		test_tcp_input(p_2_12, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 1) == 2);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 1) == 12);

		/* pass the segment to tcp_input */
		test_tcp_input(pinseq, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 1);
		EXPECT(counters.recved_bytes == 14);
		EXPECT(counters.err_calls == 0);
		EXPECT(pcb->ooseq == NULL);

		/* pass the segment to tcp_input */
		test_tcp_input(p_15_1, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 1);
		EXPECT(counters.recved_bytes == 14);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 15);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 1);

		/* pass the segment to tcp_input */
		test_tcp_input(p_15_1a, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 1);
		EXPECT(counters.recved_bytes == 14);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue: unchanged */
		EXPECT_OOSEQ(tcp_oos_count(pcb) == 1);
		EXPECT_OOSEQ(tcp_oos_seg_seqno(pcb, 0) == 15);
		EXPECT_OOSEQ(tcp_oos_seg_tcplen(pcb, 0) == 1);

		/* pass the segment to tcp_input */
		test_tcp_input(pinseqFIN, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 1);
		EXPECT(counters.recv_calls == 2);
		EXPECT(counters.recved_bytes == data_len);
		EXPECT(counters.err_calls == 0);
		EXPECT(pcb->ooseq == NULL);
	}

	/* make sure the pcb is freed */
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 1);
	tcp_abort(pcb);
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 0);
}

END_TEST static char data_full_wnd[TCP_WND];

/** create multiple segments and pass them to tcp_input with the first segment missing
 * to simulate overruning the rxwin with ooseq queueing enabled */
START_TEST(test_tcp_recv_ooseq_overrun_rxwin)
{
#if !TCP_OOSEQ_MAX_BYTES && !TCP_OOSEQ_MAX_PBUFS
	int i, k;
	struct test_tcp_counters counters;
	struct tcp_pcb *pcb;
	struct pbuf *pinseq, *p_ovr;
	ip_addr_t remote_ip, local_ip;
	u16_t remote_port = 0x100, local_port = 0x101;
	struct netif netif;
	int datalen = 0;
	int datalen2;

	for (i = 0; i < sizeof(data_full_wnd); i++) {
		data_full_wnd[i] = (char)i;
	}

	/* initialize local vars */
	memset(&netif, 0, sizeof(netif));
	IP4_ADDR(&local_ip, 192, 168, 1, 1);
	IP4_ADDR(&remote_ip, 192, 168, 1, 2);
	/* initialize counter struct */
	memset(&counters, 0, sizeof(counters));
	counters.expected_data_len = TCP_WND;
	counters.expected_data = data_full_wnd;

	/* create and initialize the pcb */
	pcb = test_tcp_new_counters_pcb(&counters);
	EXPECT_RET(pcb != NULL);
	tcp_set_state(pcb, ESTABLISHED, &local_ip, &remote_ip, local_port, remote_port);
	pcb->rcv_nxt = 0x8000;

	/* create segments */
	/* pinseq is sent as last segment! */
	pinseq = tcp_create_rx_segment(pcb, &data_full_wnd[0], TCP_MSS, 0, 0, TCP_ACK);

	for (i = TCP_MSS, k = 0; i < TCP_WND; i += TCP_MSS, k++) {
		int count, expected_datalen;
		struct pbuf *p = tcp_create_rx_segment(pcb, &data_full_wnd[TCP_MSS * (k + 1)],
											   TCP_MSS, TCP_MSS * (k + 1), 0, TCP_ACK);
		EXPECT_RET(p != NULL);
		/* pass the segment to tcp_input */
		test_tcp_input(p, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		count = tcp_oos_count(pcb);
		EXPECT_OOSEQ(count == k + 1);
		datalen = tcp_oos_tcplen(pcb);
		if (i + TCP_MSS < TCP_WND) {
			expected_datalen = (k + 1) * TCP_MSS;
		} else {
			expected_datalen = TCP_WND - TCP_MSS;
		}
		if (datalen != expected_datalen) {
			EXPECT_OOSEQ(datalen == expected_datalen);
		}
	}

	/* pass in one more segment, cleary overrunning the rxwin */
	p_ovr = tcp_create_rx_segment(pcb, &data_full_wnd[TCP_MSS * (k + 1)], TCP_MSS, TCP_MSS * (k + 1), 0, TCP_ACK);
	EXPECT_RET(p_ovr != NULL);
	/* pass the segment to tcp_input */
	test_tcp_input(p_ovr, &netif);
	/* check if counters are as expected */
	EXPECT(counters.close_calls == 0);
	EXPECT(counters.recv_calls == 0);
	EXPECT(counters.recved_bytes == 0);
	EXPECT(counters.err_calls == 0);
	/* check ooseq queue */
	EXPECT_OOSEQ(tcp_oos_count(pcb) == k);
	datalen2 = tcp_oos_tcplen(pcb);
	EXPECT_OOSEQ(datalen == datalen2);

	/* now pass inseq */
	test_tcp_input(pinseq, &netif);
	EXPECT(pcb->ooseq == NULL);

	/* make sure the pcb is freed */
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 1);
	tcp_abort(pcb);
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 0);
#endif							/* !TCP_OOSEQ_MAX_BYTES && !TCP_OOSEQ_MAX_PBUFS */
	LWIP_UNUSED_ARG(_i);
}

END_TEST START_TEST(test_tcp_recv_ooseq_max_bytes)
{
#if TCP_OOSEQ_MAX_BYTES && (TCP_OOSEQ_MAX_BYTES < (TCP_WND + 1)) && (PBUF_POOL_BUFSIZE >= (TCP_MSS + PBUF_LINK_HLEN + PBUF_IP_HLEN + PBUF_TRANSPORT_HLEN))
	int i, k;
	struct test_tcp_counters counters;
	struct tcp_pcb *pcb;
	struct pbuf *p_ovr;
	ip_addr_t remote_ip, local_ip;
	u16_t remote_port = 0x100, local_port = 0x101;
	struct netif netif;
	int datalen = 0;
	int datalen2;

	for (i = 0; i < sizeof(data_full_wnd); i++) {
		data_full_wnd[i] = (char)i;
	}

	/* initialize local vars */
	memset(&netif, 0, sizeof(netif));
	IP4_ADDR(&local_ip, 192, 168, 1, 1);
	IP4_ADDR(&remote_ip, 192, 168, 1, 2);
	/* initialize counter struct */
	memset(&counters, 0, sizeof(counters));
	counters.expected_data_len = TCP_WND;
	counters.expected_data = data_full_wnd;

	/* create and initialize the pcb */
	pcb = test_tcp_new_counters_pcb(&counters);
	EXPECT_RET(pcb != NULL);
	tcp_set_state(pcb, ESTABLISHED, &local_ip, &remote_ip, local_port, remote_port);
	pcb->rcv_nxt = 0x8000;

	/* don't 'recv' the first segment (1 byte) so that all other segments will be ooseq */

	/* create segments and 'recv' them */
	for (k = 1, i = 1; k < TCP_OOSEQ_MAX_BYTES; k += TCP_MSS, i++) {
		int count;
		struct pbuf *p = tcp_create_rx_segment(pcb, &data_full_wnd[k],
											   TCP_MSS, k, 0, TCP_ACK);
		EXPECT_RET(p != NULL);
		EXPECT_RET(p->next == NULL);
		/* pass the segment to tcp_input */
		test_tcp_input(p, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		count = tcp_oos_pbuf_count(pcb);
		EXPECT_OOSEQ(count == i);
		datalen = tcp_oos_tcplen(pcb);
		EXPECT_OOSEQ(datalen == (i * TCP_MSS));
	}

	/* pass in one more segment, overrunning the limit */
	p_ovr = tcp_create_rx_segment(pcb, &data_full_wnd[k + 1], 1, k + 1, 0, TCP_ACK);
	EXPECT_RET(p_ovr != NULL);
	/* pass the segment to tcp_input */
	test_tcp_input(p_ovr, &netif);
	/* check if counters are as expected */
	EXPECT(counters.close_calls == 0);
	EXPECT(counters.recv_calls == 0);
	EXPECT(counters.recved_bytes == 0);
	EXPECT(counters.err_calls == 0);
	/* check ooseq queue (ensure the new segment was not accepted) */
	EXPECT_OOSEQ(tcp_oos_count(pcb) == (i - 1));
	datalen2 = tcp_oos_tcplen(pcb);
	EXPECT_OOSEQ(datalen2 == ((i - 1) * TCP_MSS));

	/* make sure the pcb is freed */
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 1);
	tcp_abort(pcb);
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 0);
#endif							/* TCP_OOSEQ_MAX_BYTES && (TCP_OOSEQ_MAX_BYTES < (TCP_WND + 1)) && (PBUF_POOL_BUFSIZE >= (TCP_MSS + PBUF_LINK_HLEN + PBUF_IP_HLEN + PBUF_TRANSPORT_HLEN)) */
	LWIP_UNUSED_ARG(_i);
}

END_TEST START_TEST(test_tcp_recv_ooseq_max_pbufs)
{
#if TCP_OOSEQ_MAX_PBUFS && (TCP_OOSEQ_MAX_PBUFS < ((TCP_WND / TCP_MSS) + 1)) && (PBUF_POOL_BUFSIZE >= (TCP_MSS + PBUF_LINK_HLEN + PBUF_IP_HLEN + PBUF_TRANSPORT_HLEN))
	int i;
	struct test_tcp_counters counters;
	struct tcp_pcb *pcb;
	struct pbuf *p_ovr;
	ip_addr_t remote_ip, local_ip;
	u16_t remote_port = 0x100, local_port = 0x101;
	struct netif netif;
	int datalen = 0;
	int datalen2;

	for (i = 0; i < sizeof(data_full_wnd); i++) {
		data_full_wnd[i] = (char)i;
	}

	/* initialize local vars */
	memset(&netif, 0, sizeof(netif));
	IP4_ADDR(&local_ip, 192, 168, 1, 1);
	IP4_ADDR(&remote_ip, 192, 168, 1, 2);
	/* initialize counter struct */
	memset(&counters, 0, sizeof(counters));
	counters.expected_data_len = TCP_WND;
	counters.expected_data = data_full_wnd;

	/* create and initialize the pcb */
	pcb = test_tcp_new_counters_pcb(&counters);
	EXPECT_RET(pcb != NULL);
	tcp_set_state(pcb, ESTABLISHED, &local_ip, &remote_ip, local_port, remote_port);
	pcb->rcv_nxt = 0x8000;

	/* don't 'recv' the first segment (1 byte) so that all other segments will be ooseq */

	/* create segments and 'recv' them */
	for (i = 1; i <= TCP_OOSEQ_MAX_PBUFS; i++) {
		int count;
		struct pbuf *p = tcp_create_rx_segment(pcb, &data_full_wnd[i],
											   1, i, 0, TCP_ACK);
		EXPECT_RET(p != NULL);
		EXPECT_RET(p->next == NULL);
		/* pass the segment to tcp_input */
		test_tcp_input(p, &netif);
		/* check if counters are as expected */
		EXPECT(counters.close_calls == 0);
		EXPECT(counters.recv_calls == 0);
		EXPECT(counters.recved_bytes == 0);
		EXPECT(counters.err_calls == 0);
		/* check ooseq queue */
		count = tcp_oos_pbuf_count(pcb);
		EXPECT_OOSEQ(count == i);
		datalen = tcp_oos_tcplen(pcb);
		EXPECT_OOSEQ(datalen == i);
	}

	/* pass in one more segment, overrunning the limit */
	p_ovr = tcp_create_rx_segment(pcb, &data_full_wnd[i + 1], 1, i + 1, 0, TCP_ACK);
	EXPECT_RET(p_ovr != NULL);
	/* pass the segment to tcp_input */
	test_tcp_input(p_ovr, &netif);
	/* check if counters are as expected */
	EXPECT(counters.close_calls == 0);
	EXPECT(counters.recv_calls == 0);
	EXPECT(counters.recved_bytes == 0);
	EXPECT(counters.err_calls == 0);
	/* check ooseq queue (ensure the new segment was not accepted) */
	EXPECT_OOSEQ(tcp_oos_count(pcb) == (i - 1));
	datalen2 = tcp_oos_tcplen(pcb);
	EXPECT_OOSEQ(datalen2 == (i - 1));

	/* make sure the pcb is freed */
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 1);
	tcp_abort(pcb);
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 0);
#endif							/* TCP_OOSEQ_MAX_PBUFS && (TCP_OOSEQ_MAX_BYTES < (TCP_WND + 1)) && (PBUF_POOL_BUFSIZE >= (TCP_MSS + PBUF_LINK_HLEN + PBUF_IP_HLEN + PBUF_TRANSPORT_HLEN)) */
	LWIP_UNUSED_ARG(_i);
}

END_TEST static void check_rx_counters(struct tcp_pcb *pcb, struct test_tcp_counters *counters, u32_t exp_close_calls, u32_t exp_rx_calls, u32_t exp_rx_bytes, u32_t exp_err_calls, int exp_oos_count, int exp_oos_len)
{
	int oos_len;
	EXPECT(counters->close_calls == exp_close_calls);
	EXPECT(counters->recv_calls == exp_rx_calls);
	EXPECT(counters->recved_bytes == exp_rx_bytes);
	EXPECT(counters->err_calls == exp_err_calls);
	/* check that pbuf is queued in ooseq */
	EXPECT_OOSEQ(tcp_oos_count(pcb) == exp_oos_count);
	oos_len = tcp_oos_tcplen(pcb);
	EXPECT_OOSEQ(exp_oos_len == oos_len);
}

/* this test uses 4 packets:
 * - data (len=TCP_MSS)
 * - FIN
 * - data after FIN (len=1) (invalid)
 * - 2nd FIN (invalid)
 *
 * the parameter 'delay_packet' is a bitmask that choses which on these packets is ooseq
 */
static void test_tcp_recv_ooseq_double_FINs(int delay_packet)
{
	int i, k;
	struct test_tcp_counters counters;
	struct tcp_pcb *pcb;
	struct pbuf *p_normal_fin, *p_data_after_fin, *p, *p_2nd_fin_ooseq;
	ip_addr_t remote_ip, local_ip;
	u16_t remote_port = 0x100, local_port = 0x101;
	struct netif netif;
	u32_t exp_rx_calls = 0, exp_rx_bytes = 0, exp_close_calls = 0, exp_oos_pbufs = 0, exp_oos_tcplen = 0;
	int first_dropped = 0xff;
	int last_dropped = 0;

	for (i = 0; i < sizeof(data_full_wnd); i++) {
		data_full_wnd[i] = (char)i;
	}

	/* initialize local vars */
	memset(&netif, 0, sizeof(netif));
	IP4_ADDR(&local_ip, 192, 168, 1, 1);
	IP4_ADDR(&remote_ip, 192, 168, 1, 2);
	/* initialize counter struct */
	memset(&counters, 0, sizeof(counters));
	counters.expected_data_len = TCP_WND;
	counters.expected_data = data_full_wnd;

	/* create and initialize the pcb */
	pcb = test_tcp_new_counters_pcb(&counters);
	EXPECT_RET(pcb != NULL);
	tcp_set_state(pcb, ESTABLISHED, &local_ip, &remote_ip, local_port, remote_port);
	pcb->rcv_nxt = 0x8000;

	/* create segments */
	p = tcp_create_rx_segment(pcb, &data_full_wnd[0], TCP_MSS, 0, 0, TCP_ACK);
	p_normal_fin = tcp_create_rx_segment(pcb, NULL, 0, TCP_MSS, 0, TCP_ACK | TCP_FIN);
	k = 1;
	p_data_after_fin = tcp_create_rx_segment(pcb, &data_full_wnd[TCP_MSS + 1], k, TCP_MSS + 1, 0, TCP_ACK);
	p_2nd_fin_ooseq = tcp_create_rx_segment(pcb, NULL, 0, TCP_MSS + 1 + k, 0, TCP_ACK | TCP_FIN);

	if (delay_packet & 1) {
		/* drop normal data */
		first_dropped = 1;
		last_dropped = 1;
	} else {
		/* send normal data */
		test_tcp_input(p, &netif);
		exp_rx_calls++;
		exp_rx_bytes += TCP_MSS;
	}
	/* check if counters are as expected */
	check_rx_counters(pcb, &counters, exp_close_calls, exp_rx_calls, exp_rx_bytes, 0, exp_oos_pbufs, exp_oos_tcplen);

	if (delay_packet & 2) {
		/* drop FIN */
		if (first_dropped > 2) {
			first_dropped = 2;
		}
		last_dropped = 2;
	} else {
		/* send FIN */
		test_tcp_input(p_normal_fin, &netif);
		if (first_dropped < 2) {
			/* already dropped packets, this one is ooseq */
			exp_oos_pbufs++;
			exp_oos_tcplen++;
		} else {
			/* inseq */
			exp_close_calls++;
		}
	}
	/* check if counters are as expected */
	check_rx_counters(pcb, &counters, exp_close_calls, exp_rx_calls, exp_rx_bytes, 0, exp_oos_pbufs, exp_oos_tcplen);

	if (delay_packet & 4) {
		/* drop data-after-FIN */
		if (first_dropped > 3) {
			first_dropped = 3;
		}
		last_dropped = 3;
	} else {
		/* send data-after-FIN */
		test_tcp_input(p_data_after_fin, &netif);
		if (first_dropped < 3) {
			/* already dropped packets, this one is ooseq */
			if (delay_packet & 2) {
				/* correct FIN was ooseq */
				exp_oos_pbufs++;
				exp_oos_tcplen += k;
			}
		} else {
			/* inseq: no change */
		}
	}
	/* check if counters are as expected */
	check_rx_counters(pcb, &counters, exp_close_calls, exp_rx_calls, exp_rx_bytes, 0, exp_oos_pbufs, exp_oos_tcplen);

	if (delay_packet & 8) {
		/* drop 2nd-FIN */
		if (first_dropped > 4) {
			first_dropped = 4;
		}
		last_dropped = 4;
	} else {
		/* send 2nd-FIN */
		test_tcp_input(p_2nd_fin_ooseq, &netif);
		if (first_dropped < 3) {
			/* already dropped packets, this one is ooseq */
			if (delay_packet & 2) {
				/* correct FIN was ooseq */
				exp_oos_pbufs++;
				exp_oos_tcplen++;
			}
		} else {
			/* inseq: no change */
		}
	}
	/* check if counters are as expected */
	check_rx_counters(pcb, &counters, exp_close_calls, exp_rx_calls, exp_rx_bytes, 0, exp_oos_pbufs, exp_oos_tcplen);

	if (delay_packet & 1) {
		/* dropped normal data before */
		test_tcp_input(p, &netif);
		exp_rx_calls++;
		exp_rx_bytes += TCP_MSS;
		if ((delay_packet & 2) == 0) {
			/* normal FIN was NOT delayed */
			exp_close_calls++;
			exp_oos_pbufs = exp_oos_tcplen = 0;
		}
	}
	/* check if counters are as expected */
	check_rx_counters(pcb, &counters, exp_close_calls, exp_rx_calls, exp_rx_bytes, 0, exp_oos_pbufs, exp_oos_tcplen);

	if (delay_packet & 2) {
		/* dropped normal FIN before */
		test_tcp_input(p_normal_fin, &netif);
		exp_close_calls++;
		exp_oos_pbufs = exp_oos_tcplen = 0;
	}
	/* check if counters are as expected */
	check_rx_counters(pcb, &counters, exp_close_calls, exp_rx_calls, exp_rx_bytes, 0, exp_oos_pbufs, exp_oos_tcplen);

	if (delay_packet & 4) {
		/* dropped data-after-FIN before */
		test_tcp_input(p_data_after_fin, &netif);
	}
	/* check if counters are as expected */
	check_rx_counters(pcb, &counters, exp_close_calls, exp_rx_calls, exp_rx_bytes, 0, exp_oos_pbufs, exp_oos_tcplen);

	if (delay_packet & 8) {
		/* dropped 2nd-FIN before */
		test_tcp_input(p_2nd_fin_ooseq, &netif);
	}
	/* check if counters are as expected */
	check_rx_counters(pcb, &counters, exp_close_calls, exp_rx_calls, exp_rx_bytes, 0, exp_oos_pbufs, exp_oos_tcplen);

	/* check that ooseq data has been dumped */
	EXPECT(pcb->ooseq == NULL);

	/* make sure the pcb is freed */
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 1);
	tcp_abort(pcb);
	EXPECT(lwip_stats.memp[MEMP_TCP_PCB].used == 0);
}

/** create multiple segments and pass them to tcp_input with the first segment missing
 * to simulate overruning the rxwin with ooseq queueing enabled */
#define FIN_TEST(name, num) \
START_TEST(name) \
{ \
	LWIP_UNUSED_ARG(_i); \
	test_tcp_recv_ooseq_double_FINs(num); \
} \
END_TEST
FIN_TEST(test_tcp_recv_ooseq_double_FIN_0, 0)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_1, 1)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_2, 2)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_3, 3)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_4, 4)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_5, 5)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_6, 6)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_7, 7)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_8, 8)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_9, 9)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_10, 10)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_11, 11)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_12, 12)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_13, 13)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_14, 14)
FIN_TEST(test_tcp_recv_ooseq_double_FIN_15, 15)

/** Create the suite including all tests for this module */
Suite *tcp_oos_suite(void)
{
	TFun tests[] = {
		test_tcp_recv_ooseq_FIN_OOSEQ,
		test_tcp_recv_ooseq_FIN_INSEQ,
		test_tcp_recv_ooseq_overrun_rxwin,
		test_tcp_recv_ooseq_max_bytes,
		test_tcp_recv_ooseq_max_pbufs,
		test_tcp_recv_ooseq_double_FIN_0,
		test_tcp_recv_ooseq_double_FIN_1,
		test_tcp_recv_ooseq_double_FIN_2,
		test_tcp_recv_ooseq_double_FIN_3,
		test_tcp_recv_ooseq_double_FIN_4,
		test_tcp_recv_ooseq_double_FIN_5,
		test_tcp_recv_ooseq_double_FIN_6,
		test_tcp_recv_ooseq_double_FIN_7,
		test_tcp_recv_ooseq_double_FIN_8,
		test_tcp_recv_ooseq_double_FIN_9,
		test_tcp_recv_ooseq_double_FIN_10,
		test_tcp_recv_ooseq_double_FIN_11,
		test_tcp_recv_ooseq_double_FIN_12,
		test_tcp_recv_ooseq_double_FIN_13,
		test_tcp_recv_ooseq_double_FIN_14,
		test_tcp_recv_ooseq_double_FIN_15
	};
	return create_suite("TCP_OOS", tests, sizeof(tests) / sizeof(TFun), tcp_oos_setup, tcp_oos_teardown);
}
